Spores of S. viridochromogenes and S. griseus excrete germination inhibitors during germination. These germination inhibitors are the antibiotics produced during growth (nonactin and streptomycin, respectively). The goal is to determine the role of antibiotics in dormancy and germination of the spores. Other species will be screened for excretion of antibiotics from spores. Sensitive assays using antibiotic modifying enzymes will be employed. The nature of binding and location of streptomycin and nonactin in spores will be determined. Spores of S. griseus will be grown so that the streptomycin is specifically labeled. The spores will be disrupted and the location of label in various fractions determined. After it is determined where the antibiotics are located, and how they are found, the role they play in dormancy and timing of germination will be determined. This will involve testing for activation of releasing enzymes, determining if membrane antibiotics act as germination inhibitors and how the spores, once committed to germination, become immune to them.